Spin-Orbit Torque Detection in Insulating Low-dimensional Magnets using scanning cryo-Sagnac Interferometry and spin-filter tunneling magnetoresistance

ORAL

Abstract

Detection and quantification of current-induced spin-orbit torques (SOT) in insulating magnetic materials remains a major challenge in the pursuit of efficient magnetic memory devices. We present two complementary methods for systematic detection of SOT in insulating van der Waals magnetic heterostructures: scanning cryo-Sagnac Kerr interferometry and spin-filter tunneling magnetoresistance (sf-TMR) measurement. Sagnac selectively couples to out-of-plane magnetic moments, enabling ultrasensitive detection of current-induced magnetic deflection due to SOT on magnets with both in-plane and perpendicular magnetic anisotropy. In addition, scanning Sagnac allows for micron-scale mapping of quasi-static domain textures, offering insight into the spatial distribution of both damping-like and field-like torques. Measurement of sf-TMR further serves as a sensitive tool for detecting relative spin canting between antiferromagnetic sublattices, with potential applications in detection of sublattice-selective SOT.

*We acknowledge the funding agency, DOE BES program award number DOE DE-SC0025422 and DE-SC0021117, ARO ECP contract number W911NF2510276. Part of this work was performed at the John D. O'Brien Nanofabrication Laboratory, supported by the University of Southern California.

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Presenters

  • Ethan P Berg

    • University of Southern California

Authors

  • Ethan P Berg

    • University of Southern California

  • Derek C Bergner

    • University of Southern California

  • Andrew Koerner

    • University of Southern California

  • Isaac Mottern

    • University of Southern California

  • Tiema Qian

    • University of California, Los Angeles

  • Takashi Taniguchi

    • National Institute for Materials Science
    • Research Center for Materials Nanoarchitectonics, National Institute for Materials Science
    • International Center for Materials Nanoarchitectonics, National Institute of Materials Science, 1-1 Namiki Tsukuba, Ibaraki 305-0044, Japan
    • Research Center for Functional Materials, National Institute of Materials Science, 1-1 Namiki Tsukuba, Ibaraki 305-0044, Japan

  • Kenji Watanabe

    • National Institute for Materials Science
    • Research Center for Functional Materials, National Institute of Materials Science, 1-1 Namiki Tsukuba, Ibaraki 305-0044, Japan

  • Ni Ni

    • University of California, Los Angeles

  • Xavier Roy

    • Columbia University

  • Yunqiu (Kelly) Luo

    • University of Southern California